Cutter chain



8 11 /W JUU l N S 6 6 H U D O O G S O F C III/II Patented Sept. 27, 1938 UNITED STATES PATEN T OFFICE 2,131,188 CUTTER CHAIN Charles Osgood,

Claremont, N. H., assignor to Sullivan Machinery Company, a corporation of Massachusetts Application February 23, 1935, Serial 2 Claims. (o1. 2s2 3s) This invention relates to cutter chains and more particularly to improvements in cutter chains especially designed for use with the cutter bars of coal-cutting machines.

An object of this invention is to provide an improved cutter chain having improved means or supporting and holding a cutter bit in cutting position thereon. Another object is to provide an improved bit block and holder for the cutter bit of a cutter chain. Yet another object is to provide an improved cutter block and holder for a cutter bit of the double-ended, reversible type, having embodied therein improved means for securing the cutter bit in cutting position. A still further object is to provide a cutter bit of an improved shape. Yet another object is to provide a cutter bit of the double-ended, reversible type of an improved shape whereby the bit may be supported in an improved manner within its holder. These and other advantages of the invention will, however, hereinafter more fully appear.

In the accompanying drawing there is shown for purposes of illustration one form which the invention may assume in practice.

In this drawing,-

Fig. 1 is a side elevational view of the illustrative form of the improved cutter chain,

Fig. 2 is a cross sectional view taken substantially on line 22 of Fig. 1,

Fig. 3 is a view in longitudinal section taken substantially on line 3-3 of Fig. 2,

Fig. 4 is a plan view of the improved cutter bit,

Fig. 5 is an end view of the bit shown in Fig. 4,

Fig. 6 is a cross sectional view taken on line 6-6 of Fig. 4, I

Fig. 7 is a perspective view of the improved cutter bit.

In this illustrative embodiment of the invention there is shown a cutter chain especially designed to use with the cutter bar of a coal-cutting machine, comprising a series of bit blocks I and side straps 2 pivotally connected together at 3. The bit block I has formed in its forward face a bit-receiving socket 4 for receiving a cutter bit 5 of an improved design. Formed in the bit block and communicating with the socket 4 is a longitudinal bore 6 receiving a bolt 1 having threaded thereon at 8 a tightening nut 9, and this bolt has formed on its forward end a clamping portion ID for engaging the cutter bit 5 for firmly clamping the latter in the socket 4. The cutter bit 5 is of the double-ended, reversible type known as a detachable bit, of triangular form in side elevation and having a plane cutting face II, herein of elongated, substantially diamond-shape in contour, having itsside edges terminating at the opposite extremities of the bit in cutting points I2 and I3. The bit body is substantially triangular in shape in cross section, as shown in Fig. 6, and is formed with relatively inclined side surbit, and these plane sides I 4 of the bit body incline outwardly toward the bit points and at their outer extremities terminate at the bit points. It

the forward face of the bit block and is formed with a plane surface I! engageable with the plane face II of the bit, and the bit-receiving socket 4 is of wedge shape, formed with inclined side walls conforming with thesides I4 of the bit body and ing forwardly and outwardly from the rear wall I 8 of the socket is a wall I9 engaging the bit body in advance of the widest portion of the bit body and forming a stop for preventing the endwise release of the bit from the socket 4 when the clamp portion I0 is in its clamping position, this projection preventing bit release even when the clamp portion I0 is slightly loosened. When the cutter bit is placed in its cutting position, within the bit-receiving socket 4 and the bolt 7 tightened to move the clamp portion I0 into clamping engagement with the bit face II, the cutter bit is clamped with a wedging action in position within the socket, with the rear and' outwardly inclined edges of the bit body engaging the walls I8 and I9 of the socket and the inclined sides engaging the inclined socket walls, thereby firmly holding the cutter bit in cutting position on the' block. When the active cutting point I2 of the bit becomes dull, the clamp I0 may be loosened and the bit turned end for end within its socket, the cutting point l3 at that time being active.

As a result of this invention it will be noted that an improved cutter bit of an improved shape is provided, whereby a more effective cutting operation is attained, while at the same time simplifying the bit supporting and holding means. It

will further be noted that an improved cutter chain is provided having an improved bit block and holder, together with improved means for positively holding the cutter bit in cutting position on the chain. These and other uses and advantages of the invention will be clearly apparent to those skilled in the art.

While I have in this application specifically described one form which my invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration, and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a cutter chain, a bit block having a bitreceiving socket, a double-ended reversible cutter bit of substantially pyramidal form having an elongated, substantially diamond-shaped, plane cutting face at the base of the pyramid terminating in alined cutting points at the bit ends, said socket receiving the sides of the pyramid opposite from its base and having waiis disposed to cooperate with at least a portion of each of the bounding surfaces of said bit other than the cutting face of the latter, and securing means on the bit block and engaging the cutting face of the bit for clamping the bit in said socket.

2. In a cutter chain, a bit block having a recess in its forward face for receiving a cutter bit, a cutter bit of substantially pyramidal form having alined cutting points at the opposite ends of a plane, elongated base which is symmetrical with respect both to a major axis and to a rectan'gularly-related minor axis, the apex of the pyramid seated in said recess, the latter being shaped to conform to the shape of the bit, and a clamping member engaging the plane surface at the base of the pyramid for clamping the bit in cutting position on the block, the distance between the outermost point of clamping engagement of said clamping member with the bit and the outermost point of the recess on the block being less than the distance between the first mentioned point and the point at the pyramid apex, whereby escapeof the bit from its recess even when said clamping member is slightly loosened is precluded.

CHARLES F. OSGOOD. 

